Propeller.



G. A. sGHLo TTER.

PROPELLEP..

FILED APPLICATION JULY 7, 1911.

Patented May 20,

S-BHE 2 SHEET Aso Grone ARTHUR scnror'raa, or DRESDEN. GERMANY.

PROPELLER.

To all whom t may concern.' j

Be it known' that I, GEORG ARTriUR SoHLoTTER, a citizen of the German Empire, residing in Dresden-A., in the Kingdom of Saxony, in said Empire, have invented certain new and useful, Improvements inPropellers, of which the following is a specification.

This invention relates to propellers, and more particularly to means for increasing the efficiency there-o1. It. is also applicable to ventilators and the like. Still more particularly the object of the invention is also to increase the eiiciency in the use of the ropeller such as shown in my Letters atent No. 921,896, reissued No. 13,349, and dated January 2, 1912. The efliciency sought for is obtained by combining anoutlet-guide mechanism at the dlscharge side of the propeller-blades- For this purpose the invention consists of the combination with the propeller of a winged outlet mechanism located on the pressure or discharge side of the blades. of the propeller, said outlet mechanism consisting of stationary guide-blades which are shaped to correspond to the blades of the propeller Vbut curve7 Vn opposite direction to the same.

` The invention also consists in having the guide-blades and p `peller so arranged, that the outlet edge of tie propeller is approxi mately at right angles to the inlet-edge of the guide-blades. d

The invention consists further in the tapering rim of the outlet mechanism combined with the blades surrounded thereby.

In the accompanying drawings, Flgure 1 represents a perspective view of the outlet-mechanism of the propeller, Fig. 2 is a perspectiveview of the propeller, shown in connection with the outlet mechanism arranged at the rear or pressure-end'of the same, the shaft being in section, Fig. 3 is a diagrammatic front-view of the propeller and its outlet-mcchanism, showing the development of one blade of the same, and Fig. 4 is a vertical longitudinal section of the propeller and its outlet mechanism.

Similar letters of reference indicate corresponding parts throughout the several figures of the drawings.'

Referring .to the drawings, the hub a of the propeller has blades b, b and gradually diminishes in diameter, tapering fashion. At the end of the hub at its smallest diam- Specication of Letters Intent.

Application led July 7, 191,1T Serial No. 637,263.

Patented May20, 1913.

eter abuts a center-piece c of the outlet mechanism and forms a tapering continuation of the hub, as shown in Fig. 4. The propeller is constructed with blades that extend from the hub a which blades are preferably made according to Letters Patent No. 921,896 above referred to, but any other propeller-blades may be employed. The outlet lmechanism is arran ed adjacent to the edges of the propellerlades b and is composed `of a curved guide-blade d which,

extending from the center-piece c to a rim e surrounds the blades. The cross-section Aof the circumferential rim e tapers from its thinner outer sharp edge toward the inner edge adjacent to the blades of the propeller, as shown clearly in Fig. 4. The,edges of the curved guide-blades d of the outletmechanism cross the adjacent edges of the blades b of the propeller approximately at rio'ht angles, as shown in Figs. 2 and 3. Tie development of theguide-blades cl is indicated in the profiles 1 to 8 corresponding to the circles l:L to 81 of the guide-blades shown in Fig. 3, corresponding indications being shown in Fig. 4. The direction of rotation of the propeller is indicated by the arrow l0, while the dotted arrow 11 indicates approximately the direction of the resultant of the simultaneous lateral and axial gripping and drawing effect of the fluid, mainly in the direction of the arrow. The fluid blows through the propeller-blades and obliquely toward the axis. By the impingement of the current of the fluid, Whether it be air, water or any other fluid, on the guide-blades CZ, the change in the direction of the iiuid and the conducting of it then results. The main direction of the fluid is then indicated by the dotted arrow 12 in Fig. 3.

rlhe outlet-mechanism acts in two ways: Firstly, the eddies which impair the eiliciency are di1ninished, for the reason that the eddies which are produced by the blades of the propeller, .are cut up at the moment when they are formed; secondly, then also, the Huid which is forced by the propellerblades obliquely toward the axis, is changed in its direction and conducted by the eective surface of the guide-blades again more outwardly and so in a substantially-axial direction. Both act to obviate loss of pressure and so improve the efficiency. The second feature produces to some extent a better distribution of the fluid current on the given cross-sections of the passages between the guide-blades. This is favorably infiuenced by the relatively considerable decrease of the middle part of the given cross-section dueto the gradual narrowing of the width of the passages at *the inner ends of the guide-blades near the shaft2 while the outer zone of the assages permlts the free pas-v sage of the uid.

I claim: v

1. The combination of-aY screwropeller and an outlet-mechanism in W ich the edges of the propeller-blades are approximately at right angles to the edges of the curved vguide-blades of the outlet-mecha-A msm.

2. The combination with propeller-blades of an outlet mechanism consisting of curve outlet guide-blades at the interior thereof and having their edges ad'acent the edges of the propeller-blades, an a circumferen-l tial rim, tapered from its thicker outer portion toward its inner sharper edge and toward the edges of the propeller-blades.

In testimony, that I clalm the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

GEORG ARTHUR SCHLOTTER.

Witnesses:

O'i'ro WoLFF, RICHARD IFFERTE. 

